Let-off mechanism



A B. WEISSENBORN.

LET-OFF MECHANISM.

APPL|CATION FILED JULY 16, 1918.

1,391,435, Pat entedSept. 20,1921. i

4 SHEETS-SHEET L M E I c v //v NTOR.

ATTORNEY WITNESSES.

A. B. WEISSENBOHN.

LET-OFF MECHANISM.

APPLICATION FILED JULY 16, 1918.

1,391,435. Patentedseph 20, 1921.

4 SHEET$-SHEET 2.

/N VE N TOR A. B. WEISSENBORN.

LET-OFF MECHANISM.

APPLICATION FILED JULY 16. 1913.

1,391,435. PatentedSept. 20,1921,

4 SHEETS-SHEET 3.

WITNESSES,

ATTOPNE Y AI B. WEISSENBORN.

LET-OFF MECHANISM.

APPLICATION FILED IULY 16. 1918.

1,391,435. s pt. 20, 1921.

H 4 SHEETS-SHEET 4.

IN VE N TOR.

'TNESSES. "20%,? 4 #351 UNITED STATES PATENT orries.

ALBERT BERNARD wnIssENBoRn, or APPLETQN, WISCONSIN, nssreivono'n ONE- "HALF .ro APPLETON Winn wort-maps APIPII'ETON, WISCONSIN.

LET-Orr. MECHANISM.

Application filed July 16,

To-allwhom it may concern:

Be it-known that I, ALBERT B. WVEissnN- BORN, a citizen of the United-States,-and resident of Appleton, Outagamie county, Visconsin, have invented new anduseful Improvements in Let-Off Mechanism, of which the following is a description. reference beinghad to the accompanyingdrawQ ings, which are a part of this specification.

This invention relates to let-off mechanism for looms, particularly wire-weaving looms vsuch as looms for weaving Fourdrinier wires, and has for itsobject to auto matically reposition the, tension lever connection with the warp beam as the wire is drawn off of the latter'so as to maintain a predetermined 'tensioning effect on the warp wires,

Another object for the invention is to utie lize thepsoiliation of the tension lever inci dent to the -operation of, the loom to control apower'means for'lettin'g off the warp wires by changing: the position of the connection of the tension lever with the-warp beam.

Another object of the invention is to provide synchronously operated adjusting means at both ends ofthe warp beam.-

A-nother object-of the invention is to vary the degree of-readjustment accomplished by the operation ofthe power means to suit the requirementsoffabrics of different mesh. 'With'the above and other objects in view the invention consists in the. let-off mechanism ashereinclaimed and all equivalents.

Referri-ng to-theaccompanying drawings, in which like characters of reference'indicate --the-same parts in different views:

Figure 1 is aside view ofa loom :provided with the-automatic let-off mechanism of this invention; a

Fig. 2 is-a-n enlarged view of the let-off mechanism; r a

Fig. 3 is a front view of the warp beam with the let-off mechanism applied thereto I Fig. 4 is a-sectional detail view of "the power-operated means forturning the worm Share I Fig. 5 is a sectional plan view thereof; and, f

Fig; (Sis-a detail view of the air valve. .In these drawings 10 indicates the side frames of the loom between; which are mounted the warp beam 11, the breast-beam 12 and receiving-roll 13, as usual. The

Specification of Letters Patent.-

Patented Sept. 20, 1921.

1918. Serial Nos-245,170.

swinging lay 14-operates as usual to beat up the weft wire left by the shuttle in its travel through the shed formed between the warp wires 15 by the alternate *reciprocation of the heddles, and suitable'means -is provided for operating the receiving roll 13 to wind the/fabric thereon as it is woven.

Tension isgiven to'thewarp wires 15 by means giving the warp beam 11 a-tende'ncy to turn backwardly or in a directionto rewind the wires thereon and it is thiste'nsion means, capable of changing its'poin't of connection with'th'e warp beam to permitthe wires being unwound therefrom without materially varying the tension, that constitutes the present invention. 7 At each end of'theshaft 16 of'the warp beam 11 is fixed a worm wheel 17 ,andeach worm wheel meshes with a worm 18 on a vertical shaft 19 slidably'mounted in's'u'itable bearings and having'swivel connection with a block20 pivotally mountedbetween a pair of links '21suspended'from a merges which is fulcrumed at 23 'on the frame.

worm wheels 17.

Loosely mounted in the lower bearing 28 of each'shaft 19 is a sleeve'29 splined'on the shaft 19, permittingthe shaft tofreely'slide within it but compelling it to turn 'therewith. A projection 30 on the bearing ontering a groove'of the'sleeve holds the. sleeve against vertical displacement. v

v A bellcrank 31, fitting-in another groove of-the sleeve 29, carrieswaspring-pressed pawl 32 on one arm' to engagetheteeth of'a ratchet disk 33' formed on or-secured tothe sleeve 29. The other arm ofthe bell crank 31 has an upstanding stud 34 and *a eonnecting rod-35 connectsthe stud 34 on one side of theloom withthe corresponding stud .34 on the other side ofthefloom so tlmtbth of the bell cranks move together for producing the same efiect at both ends of the warp beam.

on one of the bearings 28 is a bracket 36 supporting a cylinder 37 in which there is a piston 38 connected by a connecting rod 39 with the upstanding stud 34 of the bell crank. It is under the influence of pressure fluid, such as compressed air, in the cylinder that the piston serves to swing both bell cranks 31 to turn the shafts 19 through the engagement of the pawls with their ratchets. The return movements are caused by a coil spring'4O connected with the connecting rod -and Witha stationary support. The degree of movement of the bell cranks 31 with each operation may be varied by the turning of an" adjusting screw 41 forming a stop for engaging one arm of one of the bell cranks L V and forming a stop'therefor. This set screw 41 is threaded through a removable post 42 which may be changed in its position on the bearing by placing it in another opening 43 thereof to increase the range of adjusta bility. I r

For automatically controlling the supply of compressed air or other pressure fluid to the cylinder 37, a roller 44 projecting from lever 22 is adapted in itsdownward movement to engage a roller 45 on one arm of a bell crank 46 fulcrumed on the frame 10.

' The other arm'of the bell crank 46 is'connected by a'valve rod 47 with a valve on the cylinder 37. The valve construction, which I V is best seen in Figs. 4 and 6, comprises a cas- 1n' 48*form1ng a valve chamber with a va ve seat between a port 49 leading to the interior of the cylinder and a port communicating with a compressed air supply pipe 50. A spring-p-ressedvalve member 51'is seated on the valve seat and'has a tubular stem 52 projecting therefrom and passing through a forming a seat at its lower end for a member 54 which has a spherical self-centering base portion resting on the seat and a stem 55 passing downwardly through an opening in the seat. This member istubular atits up- I per portion or cup-shaped to ;fit around the tubular valve stem 52 and form a telescoping connection therewith. Aleather plug or oth'ervalv'e material 56 is contained in the bot-tom of the cup-like socket of'member 54 to-form a tight-fitting connection with the end of the tubular stem and prevent the passage of air therethrough when the yoke 1s lifted by the valve rod for unseating the tion of the weight 27 tending to lift the worm 18 by means of the lever 22 and thus imparting a tendency to the warp'beam to turn backwardly. As the wire is drawn off of the warp beam during the operation of V the loom this tendency has to be overcome and the Worm with its shaft 19 is moved downwardly, causing the weight to rise. At a certain point in the travel of these parts shed are given the proper tension by the ac-- the roller 44 on lever 22 engages the roller 1 45 onbell crank 46 causing the valve rod to be lifted until it unseats the valve 51. This admits compressed. air tothe' cylinder 37, while the exhaust is closed by the engagement of the valve face 56 with the end of] the tubular valve stem 52, and consequently the piston 38 is moved outwardly causing both bell cranks 31 toswin-g and feed the ratchet disks and the shafts 19 a distance determined by the position'of the stops 41.

Such turning of the shafts 19 threads the worms 18 to higher positions en'the worm wheels of the warp beam without interrupting the tensioning. -This upward movement of the shafts 19 causes a corresponding-low ering of the weights 27 and also causes the disengagementof the rollers 44 and 45 permitting the air valve-to again close and opening the exhaust from the cylinder so that spring 40 restores the bell cranks 31 to. their original positions ready for the next feeding operation. r

The degree of movement of the various parts is not great, for the worms are only given a fractional turn with each. operation.

Under normal conditions when the lay carrying the reed beats up a weft wire, the; concussion causes lever 22 to 'momentarily drop. It is this momentary depression which is used to accomplish the governing of the tension device. Under normal weaving when the shed is open, the lever 22 isdepressed slightly but possibly not enough for the accomplishment of the let-off regulation,

butwhen the blow is struck the depression of lever 22 is sufficient to cause the opening of valve 51 and an operation of the piston, producing a let-off.

One important feature of this-invention is that the tension lever 25 is always main- 'tained in an approximatelyyhoriz ontal po-' sition to maintain the tension approximately uniform. I V

In weaving fabric of different mesh it is necessary to adjust the let-off so that it will let off more warp than is needed. It is prao tically impossible to get a sufficientlyeven adjustment so as to let off the exact amount required. Various causes influence the imam-mes amount of warp wire required for awgiven length of fabri'c of a certain Emesh; If'the weft wire differs ailittle in itemperlit will take up-lmore or less warpp. Another reason istthat whena-new wire is-started, and as the weaving progresses, the woven cloth piles up on "the receiving-roll so that-there must be-some method of compensating for 45 for the operation of the let-ofi.

In accordance with the provisions of the patent statutes I have described the principle of operation of my invention together with the apparatus which I now consider to represent the best embodiment thereof; butI desire it to be understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means within the scope ofmy claims. 1

lVhat I claim as new and desire to secure by Letters Patent is: 4

1. In a loom, a warp beam, a tension lever having connection therewith for turning same backwardly, and means actuated by the play of'the tension lever for varying the connection between the tension lever and the warp beam to produce a let off.

2. In a loom, a warp beam, a tension lever having connectlon therewlth, and fluid pres sure-operated means for varying the connection between the tension lever and the warp beam for producing a let off, said means being actuated by the movement of the tension lever.

3. In a loom, a warp beam, a tension lever having connection therewith, a trigger in the path of the tension lever, and fluid pressureoperated means controlled by the trigger for changing the connection between the tension lever and the warp beam for producing a let ofl". I

4:. In a loom, a warp beam, a tension lever having connection with the warp beam, means for adjusting the connection between the tension lever and the warp beam, a compressed air cylinder for operating said means, and a valve controlling the pressure in the cylinder and operated by the movements of the tension lever.

5. In a l0om,. a warp beam, a tension lever a worm connection between the tension lever and the warp beam, through which the tension lever may turn the warp beam backwardly, and means actuated by ithe movements of the tension lever for turningthe 6. In aloom, a warp beam, atension lever, a worm wheel on the warp beanna worm connected with the tension lever andtmeshing with the worm wheel, fluid pressure operated means for turning the worm, and a valve :actuated by the movements of the' tension lever for controlling'the fluid:pressureoperated means.

.7. :In'agloom, a warp a wormwheel on the warp beam, a worm meshing With the worm wheel and 'having swivel connection with-the tension lever, a

ratchet wheel-"carried by'the worm,a swinging pawl 'engagingthe ratchet wheel,fifluid pressure means for swinging thep-awl, and a valve operated by the movements ofnthe tension lever ifor controlling the f fluid Ypressure means.

8. In a loom, a warp beam, a tension lever, a worm wheel connected with the Warp beam, a worm meshing with the worm wheel and having swivel connection with the tension lever, a ratchet wheel carried by the worm, a swinging pawl engaging the ratchet wheel, a compressed-air cylinder having its piston connected with the swinging pawl, a valve controllin the supply of compressed air to the cylin er, and a trigger operated by the tension lever for controlling the valve.

9. In a loom, a warp beam, a tension lever having connection with the warp beam, power-operated means operated by the movements of the tension lever for changing the position of the connection between the tension lever and the warp beam, and adjustable means for varying the degree of such change.

10. In a loom, a warp beam, a tension lever, a worm connection between the tension lever and the warp beam for turning the warp beam backwardly, power means oper ated by the movements of the tension lever for turning the worm, and adjustable means for varying the degree of movement imparted to the worm by the power means.

11. In a loom, a warp beam, a tension lever, a worm wheel connected with the warp beam, a worm meshing with the worm wheel and connected with the tension lever, a ratchet wheel carried by the worm, a swinging pawl engaging the ratchet wheel, fluid pressure-operated means for moving the swinging pawl, a valve operated by the movements of the tension lever for controlling the fluid pressure-operated means, and

an adjustable stop for limiting the movebeam, a tension'lever,

bearings in which the worm is slidably mounted, a sleeve splined onthe worm, a ratchet wheel fixed on the sleeve, a bell crank mounted on the sleeve, a pawl carried thereby meshing with the ratchet wheel, an ad justable stop mounted on a bearing and engaged by the bell crank, a cylinder with its piston connected with the bell crank, and means for controlling a supply of fluid pressure to the cylinder. V

13. In a loom, a warp beam, a worm wheel thereon, a worm meshing with the worm wheel and slidably mounted in bearings, a tension lever with which the worm has a'swivel connection, a compressed air cylinder, ratchet means operated by the movements of the piston-thereof for turning the Worm, a valve casing having connections with the cylinder and a source of compressed air supply and provided with a Valve seated between such 1 with the cylinder connection, a roller com I nected with the tension lever, a bell crank having a roller engaged by the first mentioned-ro1ler, a valverod suspended from the bell crank, a yoke on the valve rod, a

cup-shaped member seated in the yoke and receiving the tubular valve stem, and a valve face in the cup-shaped member for closing the end of the tubular valve stem when the cup-shaped member is moved to force valve oil of its seat. V

In testimon U whereof I afiix my signature in presence 0 two witnesses.

v ALBERT BERNARD -WEISSENBORN.

lVitnesses: V

. G. E. BUCHANAN,

W. H. JAHNKE.

the 

